These horses are the famous Lipizzaner stallions from the Spanish Riding School in Vienna Austria. On the back of this card, where the message would normally be written, there is an ad for a performance at the Sportpaleis Antwerpen in Antwerp, Belgium.
The Spanish Riding School - Vienna Austria. i would KILL to study at this riding school! I read about it and it takes years to fully complete the training. I'd love to but thats a long time in friggen Austria.